Recursion in computer science is a method of problem solving where the solution to a problem depends on solutions to smaller instances of the same problem.

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45 views

Recursive function for listing directories [on hold]

The below code is recursive function that list directories in 2 levels: ...
3
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1answer
53 views

Recursively reading a directory in node.js

I made a function for recursively reading a directory and it just seems kind of long and complicated. If you could take a look and tell me what's good or bad about it, that would be great. Reading ...
3
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2answers
95 views

Recursive uniform cost search that needs to be optimized

I have this uniform cost search that I created to solve Project Euler Questions 18 and 67. It takes the numbers in the txt file, places them into a two dimensional list, and then traverses them in a ...
7
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1answer
96 views

Linked List reversal

Recursive version. The only interesting function: The original version: ...
6
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2answers
83 views

Ray Tracer main loop

For the past week I have been studying and improving a ray tracer that I ported from JavaScript. The bare finished port was only exactly what was written in JavaScript and rendered at around 20fps at ...
4
votes
5answers
152 views

Validating that all Open/Close Parentheses are correctly matched

It returns true for: a*(b+c) ()() (()) ((!!(123(x)))) and returns false for (a((b+c)) )()( ))(( (rsd+3)*(-3-a)) ...
9
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2answers
85 views

Printing permutations of a given string

I want some feedback on the program I developed in C for printing the permutations of a given string. ...
5
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1answer
64 views

recursive function : filtering large multidimensional array by key element to HTML list

I have a multidimensional array as a result from a webservice called from PHP. I cannot edit the webservice, but the result is as ...
4
votes
1answer
64 views

Is recursion like this safe with a task queue on GAE?

I've written a function to call with the deferred library to generate a large task queue, and at first without the recursion it timed out (deadlineexceeded) so now I'm trying with a recursion but is ...
2
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0answers
16 views

Completing a Graph in Scheme

For the record, this is part of a homework assignment, but I have already implemented a solution. I am simply wondering if there is a better way to do it. Background: I am asked to write a procedure, ...
9
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3answers
191 views

Recursive Fibonacci with Generic delegates

Here is fast recursive fibonacci like for loop. How it be more readable and is possible remove TArg's ? ...
7
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5answers
708 views

Efficient pathfinding without heuristics?

Part of my program is a variable-sized set of Star Systems randomly linked by Warp Points. I have an A* algorithm working rather well in the grid, but the random warp point links mean that even though ...
8
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2answers
107 views

Finding path in Maze

I recently gave an interview and was asked the following question. I posted this here Finding path in Maze also, and someone suggested I should try Code Review. So here it goes. A maze is a group of ...
5
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2answers
139 views

Map color problem: Optimize using a heap?

I've written some python code to solve the map coloring problem. In my code, I represent the problem using Territory and ...
12
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3answers
347 views

Improving knapsack branch and bound: how to forward filter?

I've coded branch and bound to solve the knapsack problem, and use a greedy linear relaxation to find an upper bound on a node I'm currently exploring. What I mean by this is that I first sort the ...
6
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1answer
76 views

Functional, but not recursive, tree traversal

To learn tree traversal i implemented os.walk, tail-recursive and stack-based. Unfortunately Python doesn't support tail call optimization. How do i rewrite my ...
7
votes
2answers
407 views

Can this recursive binary search in C be made more concise?

Can someone please let me know if they see glaring issues with this code? I tested a handful of cases and it seems to work but in other threads. I often see much more concisely written versions of ...
4
votes
2answers
153 views
0
votes
1answer
109 views

Solving a Recursive method with Mazes [closed]

Given any map such as the one below, 1 for path and 0 for walls, can you guys review my code and see what I am doing wrong. My code is supposed to return an arrayList of the positions that it passed ...
0
votes
1answer
52 views

Solving a Recursive Maze method [closed]

Given any map such as the one below, 1 for path and 0 for walls, can you guys review my code and see what I am doing wrong. My code is supposed to return an arrayList of the positions that it passed ...
7
votes
1answer
153 views

Web service proxy that switches endpoint URLs in the event of a TimeoutException

I am creating a service (FaultTolerantCommunication) that wraps a call to a (web) service. Its responsibility is to switch the endpoint URL in the event of a ...
5
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2answers
269 views

QuickSort of Comparable[]

Here is the code for the QuickSort class that I created. ...
2
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2answers
66 views

Algorithms for traversing unordered tree

I have been doing some programming 'exercises'. I'm trying to come up with the most efficient algorithm for tree traversal. Consider the following function signature: ...
11
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1answer
87 views

Recursive calculator in C

This is a calculator I wrote for a student's project. It still has a problem (one that I know of), where it can't handle inputs of the form 2*2*2... (more than one ...
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3answers
185 views

Lowest common ancestor in recursive tree traversal

LCA = Lowest Common Ancestor The following code finds the lowest common ancestor in tree of nodes, where a node can have two parents, left and right. The tree looks like this: ...
9
votes
2answers
288 views

Math expression solver

Recently I've stumbled upon an interesting challenge for me. You should develop C application, that solves math expressions. Operations such as (+,-,*,/) should be supported, as well as (cos, sin, ...
6
votes
3answers
100 views

Iteration to recursive function

In my first iterative algorithm, I do this ...
4
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2answers
106 views

Numeric expression parser - calculator

In particular, if someone could describe a better way to go from the tokenized list to the Expression tree, it would be super helpful. I would like to get rid of the casting in the parser but am not ...
12
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5answers
1k views

Identifying first negative number in array of doubles

I was asked to create a function that checks if an array of doubles has all negative numbers or none. If these 2 (all negative, all positive) are false, check the ...
6
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1answer
258 views

Tower of Hanoi solver

Requesting code review, best practices, optimizations for this solution to the Tower of Hanoi problem. ...
2
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3answers
142 views

To check if a string C is an interleaving of A and B Code

This is my code to check if a string C is an interleaving of Strings A and B. Please suggests optimizations, and where I can improve. ...
14
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4answers
698 views

Displaying each number of an integer in a sequence

One of the books I'm currently reading to learn C# asked me to write a method that takes an integer between 1 and 99999 and displays each number in that integer in a sequence, separating each digit by ...
0
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2answers
36 views

Generic sequence splitter in Common Lisp

I wrote a function split-seq-by-n which accepts a sequence and a number and splits the sequence into subsequences of length n (the last subsequence getting the ...
11
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6answers
586 views

Help refactor this to be less procedural and more recursive

Reference: Is this a faithful rendition of the selection sort algorithm? I'm working through an elementary book on sort and search algorithms, and writing some sample code to test my understanding. ...
7
votes
2answers
192 views

Is this non-recursive mergesort efficient and a good way to simulate the recursive version?

My teacher assigned us to do the recursive version of mergesort, yet I heard that the non-recursive version (bottom up) is a bit tougher, so I decided to this one as well. My main concerns are: ...
5
votes
2answers
135 views

Optimize disk enumeration and file listing

I am writing C++ code to enumerate whole HDD and drive listing. However, it takes more than 15 minutes to complete the disk enumeration of all drives (HDD capacity 500GB) and compile the response in ...
2
votes
3answers
103 views

Python script to touch files of a particular pattern in all folders of a given name

The intent of this script is to hunt down all "*/testResults/*.xml" files and touch them, so that our build system doesn't issue errors that the files are too old ...
5
votes
3answers
103 views

Pair matching elements from two lists

Here is a method that takes two lists (l1 and l2) and pairs up elements that "match". As you can see at the end of the code ...
5
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2answers
98 views

Recursive reverse function

Write a recursive version of the function reverse(s), which reverses the string s in place. Here is my solution: ...
8
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3answers
205 views

Integer-to-string conversion using recursion

Adapt the ideas of printd to write recursive version of itoa; that is, convert integer into a string by calling a recursive ...
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votes
1answer
75 views

Recursively calculating powers of numbers [closed]

In this program, I understood everything except power(x1,y1-1). I want to know how the power(x1,y1-1) function exactly works. ...
1
vote
1answer
48 views

replacing explicit recursion with a fold

as an exercise I wanted to rewrite this toy python code in haskell. ...
7
votes
1answer
143 views

Suggestions needed for alternative methods of solving sudoku

I am new to programming as well as this site. I am learning Java as my first programming language. I have written a bit of code (of course after struggling a lot). I would love to read expert reviews ...
0
votes
0answers
72 views

REST Response: Checking for Success and Error

I thought this was pretty slick - maybe not, I just wanted to share and maybe get some feedback: As part of a REST client class: Accepts the JSON response from REST or REST-like service, searches ...
3
votes
3answers
540 views

Reversing a string in-place - recursion or iteration?

I am practicing my recursion skills as I think I am really weak in this area. I have written the following Java class whose purpose is to reverse a string but to do it 'in-place' - i.e. no additional ...
4
votes
1answer
77 views

Using a function recursively to calculate higher-order derivatives

I am writing a code to do some numerical task using the routines of Numerical Recipes book. One of my objectives is to calculate the second derivative of a function and I have a routine that ...
3
votes
2answers
108 views

Custom UI - Seeing which control has focus

I'm trying to make a simple UI to better understand how interfaces and the System.Windows.Forms Controls behave. Like the above namespace, I will be able to get ...
5
votes
1answer
105 views

A Program that Finds Empty Folders

I wrote a program that finds empty folders and subfolders in a directory. It's the first program I've ever written in Java, and I'd like some critique. I feel like I'm not utilizing classes in a very ...
4
votes
1answer
83 views

Printing all strings in a Boggle board

I am trying to print all the strings given in a N x N Boggle board. Its basically a N x N scrabble-like board where words can be made from a position - horizontally, vertically and diagonally. Here ...